Senaranya HL7 Versions Save

Allow array on setPatientIdentifierList field (PID.3)

• Added segment-classes for PD1, RX4 & RXR

This change is required to support HL7 v2.7 onwards

• HL7 factory class provides a more fluent, object-oriented interface for parsing or composing a message, allowing you to chain multiple methods together using a more readable syntax compared to calling new Message()
• Updated readme

1. Added data-types for method arguments, method returns and properties
2. Code cleanup
3. Added 2 tests for doNotSplit argument in Message() constructor

• Upgraded php version to 8.0+
• Declare strict. More type checking to be followed in coming releases
• Remove redundant phpdocs
• Other code cleanups